Cetirizine is a second-generation peripherally selective antihistamine used to treat allergic rhinitis (hay fever), dermatitis, urticaria (hives), and runny nose. [11]. It is taken by mouth. [12]. Effects generally begin within thirty minutes and last for about a day. [12]. What it is: Cetirizine (Zyrtec)—second-generation antihistamine for hay fever and hives. Typical dose: 10 mg once daily; 5 mg may suffice for mild symptoms or kidney impairment. Cetirizine is a second generation antihistamine that reduces the natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, watery eyes, and runny nose. Cetirizine is used to treat cold or allergy symptoms such as sneezing, itching, watery eyes, or runny nose. From the 1 doctor and allergist recommended OTC allergy brand when it comes to oral antihistamines, Zyrtec Tablets contain 10 mg of Cetirizine HCl to help relieve indoor and outdoor allergy symptoms caused by dust, pet dander, and pollen. Whether you need to know ZYRTEC ® dosages for adults or children, check out our dosing charts and FAQs for the ZYRTEC ® family of products, to find all the information you need. Learn about cetirizine (Zyrtec) usage and dosing. Read the latest news and reviews about the drug as well as potential side effects and popular alternatives. Zyrtec (cetirizine) provides rapid symptom relief for seasonal/perennial allergic rhinitis and hives. It is generally well tolerated; however, mild drowsiness can occur in some patients compared with fexofenadine or loratadine. Zyrtec is used in adults and children to treat cold or allergy symptoms such as sneezing, itching, watery eyes, or runny nose. Zyrtec is also used to treat itching and swelling caused by chronic urticaria (hives). What do Zyrtec products treat? Zyrtec products are commonly used to treat allergy symptoms such as runny nose, itchy/watery eyes, sneezing, or an itchy nose or throat. The main active ingredient in. Overview: Cetirizine is an antihistamine that is taken to help treat allergy symptoms, such as a runny nose, itchy or watery eyes, sneezing, or an itchy nose or throat. It may also be used to.